Campbell CR850, Руководство оператора

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Section 7. Installation
120
Table 10. Data Types
Name:
Command
or
Argument
Description /
Word Size
Where Used Notes Resolution / Range
As Boolean
BOOLEAN
Signed Integer /
4 byte
Dim & Public
variables
Final data storage
Use to store TRUE or FALSE states,
such as with flags and control ports. 0 is
always false. -1 is always true.
Depending on the application, any other
number may be interpreted as true or
false. See
True = -1, False = 0 (p.
145).To save memory, consider using
UINT2 or BOOL8 .
0, -1
BOOL8
Integer /
1 byte
Final data storage
8 bits (0 or 1) of information. Uses less
space than 32-bit BOOLEAN. Holding
the same information in BOOLEAN will
require 256 bits. See
Bool8 Data Type
(p. 228).
0, -1
NSEC
Time Stamp /
8 byte
Final data storage
Divided up as four bytes of seconds
since 1990 and four bytes of
nanoseconds into the second. Used to
record and process time data. See
NSEC
Data Type (p. 224).
1 nanosecond
As String
STRING
ASCII String /
word size varies
Dim & Public
variables
Final data storage
Size is defined by the CR800 operating
system. When converting from
STRING to FLOAT , numerics at the
beginning of a string convert, but
conversion stops when a non-numeric is
encountered. If the string begins with a
non-numeric, the
FLOAT will be NAN .
If the string contains multiple numeric
values separated by non-numeric
characters,
SplitStr() can be used to
parse out the numeric values. See String
Operations (p. 237) and Serial I/O (p.
201).
Unless declared otherwise, the minimum
string size is 16 bytes or characters. Size
above 16 bytes increases in multiples of
four bytes; for example,
String * 18
allocates 20 bytes (19 usable).
CRBasic Example 9. Data Type Declarations
'Float Variable Examples
Public Z
Public X As Float
'Long Variable Example
Public CR800Time As Long
Public PosCounter As Long
Public PosNegCounter As Long
Boolean Variable Examples
Public Switches(8) As Boolean
Public FLAGS(16) As Boolean
'String Variable Example
Public FirstName As String * 16 'allows a string up to 16 characters long